Dirty Talking?

So this morning my boyfriend and I were messing around in bed and he asked 'what are you going to do to me?' (Sorry tmi). So I just sort of giggled my way through it. I've never talked dirty or had anyone do that to me. So I'm sort of at a total loss. I have no clue what to say in that situation. All I could think of was the correct/medical terms for everything which just isn't sexy. I think it could help spice up our sex life so any advice would be really appreciated!